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Two Rab2 interactors regulate dense-core vesicle maturation.

ABSTRACT: Peptide neuromodulators are released from a unique organelle: the dense-core vesicle. Dense-core vesicles are generated at the trans-Golgi and then sort cargo during maturation before being secreted. To identify proteins that act in this pathway, we performed a genetic screen in Caenorhabditis elegans for mutants defective in dense-core vesicle function. We identified two conserved Rab2-binding proteins: RUND-1, a RUN domain protein, and CCCP-1, a coiled-coil protein. RUND-1 and CCCP-1 colocalize with RAB-2 at the Golgi, and rab-2, rund-1, and cccp-1 mutants have similar defects in sorting soluble and transmembrane dense-core vesicle cargos. RUND-1 also interacts with the Rab2 GAP protein TBC-8 and the BAR domain protein RIC-19, a RAB-2 effector. In summary, a pathway of conserved proteins controls the maturation of dense-core vesicles at the trans-Golgi network.

SUBMITTER: Ailion M

PROVIDER: S-EPMC3997996 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Two Rab2 interactors regulate dense-core vesicle maturation.

Ailion Michael M Hannemann Mandy M Dalton Susan S Pappas Andrea A Watanabe Shigeki S Hegermann Jan J Liu Qiang Q Han Hsiao-Fen HF Gu Mingyu M Goulding Morgan Q MQ Sasidharan Nikhil N Schuske Kim K Hullett Patrick P Eimer Stefan S Jorgensen Erik M EM

Neuron 20140401 1

Peptide neuromodulators are released from a unique organelle: the dense-core vesicle. Dense-core vesicles are generated at the trans-Golgi and then sort cargo during maturation before being secreted. To identify proteins that act in this pathway, we performed a genetic screen in Caenorhabditis elegans for mutants defective in dense-core vesicle function. We identified two conserved Rab2-binding proteins: RUND-1, a RUN domain protein, and CCCP-1, a coiled-coil protein. RUND-1 and CCCP-1 colocaliz ...[more]

PMID: 24698274

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